Eu tenho tela comScrollView e três diferentesLinearLayouts.

1LinearLayout contém umSpinner e segundo contémListView e terceiro contém doisButtons (horizontal).

Eu quero exibir uma tela que contém 3LinearLayouts sempre exibido na parte inferior da tela e 1LinearLayout sempre exibido no topo. Na parte do meio, eu quero exibirListView conteúdo. Então, na tela inteira, não há espaço em branco presente.

Quero criar uma tela para vários dispositivos com tamanhos diferentes.

     <?xml version="1.0" encoding="utf-8"?>
     <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@drawable/backrepeat"
android:orientation="vertical" >

<include
    android:id="@+id/include1"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    layout="@layout/actionbar" >
</include>

<ScrollView
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:scrollbars="horizontal" >

    <LinearLayout
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        android:orientation="vertical"
        android:padding="10dp" >

        <LinearLayout
            android:layout_width="fill_parent"
            android:layout_height="fill_parent"
            android:layout_weight=".2"
            android:background="@drawable/rounded_border"
            android:orientation="vertical"
            android:padding="15dp" >

            <TextView
                android:id="@+id/tvDiaryData"
                style="@style/greenstyle"
                android:layout_width="fill_parent"
                android:layout_height="wrap_content"
                android:background="@drawable/heading"
                android:gravity="center_horizontal"
                android:text="@string/tvDiaryData" >
            </TextView>

            <TextView
                android:layout_width="fill_parent"
                android:layout_height="10dp"
                android:gravity="center_horizontal" >
            </TextView>

            <Spinner
                android:id="@+id/spDiaryAllBooking"
                android:layout_width="fill_parent"
                android:layout_height="wrap_content"
                android:prompt="@string/select_diaryallbooking" />
        </LinearLayout>

        <LinearLayout
            android:layout_width="fill_parent"
            android:layout_height="fill_parent"
            android:layout_weight="1.6"
            android:background="@drawable/layerlist"
            android:orientation="vertical"
            android:paddingBottom="5dp"
            android:paddingLeft="15dp"
            android:paddingRight="15dp"
            android:paddingTop="5dp" >

            <ListView
                android:id="@+id/lvDiaryBooking"
                android:layout_width="fill_parent"
                android:layout_height="fill_parent"
                android:divider="#636466"
                  android:layout_weight="1"
                android:dividerHeight="1dip"
                android:scrollbarStyle="outsideOverlay"
                android:scrollbarThumbVertical="@drawable/scrollbar_vertical_thumb" />
        </LinearLayout>

        <LinearLayout
            android:layout_width="fill_parent"
            android:layout_height="wrap_content"
            android:layout_weight=".2"
            android:background="@drawable/rounded_border"
            android:orientation="horizontal"
            android:padding="10dp" >

            <Button
                android:id="@+id/btnDiaryBook"
                style="@style/greenButton"
                  android:layout_weight="1"
                android:layout_width="wrap_content"
                android:layout_height="fill_parent"                    
                android:onClick="btnDiaryBook_Click"
                android:text="@string/btnBook" >
            </Button>

            <Button
                android:id="@+id/btnDiaryBalance"
                style="@style/greenButton"
                  android:layout_weight="1"
                android:layout_width="wrap_content"
                android:layout_height="fill_parent"
                android:layout_marginLeft="10dp"                 
                android:onClick="btnDiaryBalance_Click"
                android:text="@string/btnDiaryBalance" >
            </Button>
        </LinearLayout>
    </LinearLayout>
         </ScrollView>

     </LinearLayout>

Layout de tela com o que eu quero: